Indolent primary cutaneous B cell lymphomas (PCBCL) generally have a good prognosis, but they often relapse leading in some cases to extracutaneous disease and therefore, to poor survival. We developed a prognostic model to improve the therapeutic approach to these lymphomas. Two hundred and seventeen patients with diagnosis of indolent PCBCL stage IE or IIE were assessed retrospectively. The prognostic model was built to fit a Cox proportional hazard model using all the covariates affecting progression-free survival (PFS) at p<0.1 in the univariate analysis, and the final model was selected based on the Bayes Information Criteria. Elevated serum lactate dehydrogenase, morphology of the lesion (nodule vs. other), and >2 lesions were independent predictors for PFS. To each prognostic factor was assigned a value of 1. Patients were then stratified to three risk groups: score 0 (28%), low risk; score 1 (55%), intermediate risk; score 2 and 3 (17%), high risk with a 5-year PFS of 91%, 64%, and 48%, respectively (p<0.001). The CLIPI is an easily applicable prognostic index and represents a promising tool for risk-adapted treatment strategies. However, it needs to be addressed in prospective clinical studies.